All Cisco IP Phones models require an 802.11d and 802.11h to be enabled on the access point to connect.

When 802.11d is enabled on an AP, it starts adding country information element to beacons, probe requests, and probe responses. The country information elements simplifies the creation of 802.11 wireless access points and client devices that meet the different regulations enforced in various parts of the world.

When 802.11h is enabled on an AP, it solves problems like interference with satellites and radar using the same 5 GHz frequency band. The standard provides Dynamic Frequency Selection (DFS) and Transmit Power Control (TPC) to the 802.11a PHY. TPC ensures that the average power is less than the regulatory maximum to reduce interference to satellites. 802.11h requires 802.11d to be enabled.

Aruba Access Point running on default configuration do not advertise its 802.11d (Country Information) and 802.11h (Transmit Power Control) capabilities as they are disabled by default.

Below are the GUI and CLI screenshots, that show how to enable 802.11d and 802.11h in the configuration:

Note: In the above screenshots, "default" 802.11a radio profile was taken for demo. In real deployments, enable on the radio profile which is associated to the access points where Cisco IP phones connect.

Below is the "Show" command, to verify if 802.11d and 802.11h capabilities are enabled:

Below screenshot show how to enable, 802.11d and 802.11h capabilities on Instant AP (IAP):